The ancient Banaue rice terraces in the Philippines are being destroyed. By giant worms.

Cut into near-vertical slopes by the Ifugao people of northern Luzon, the water-filled levels curve around the hills' maze-like contours, their waters reflecting the pale green of freshly-planted rice stalks. But since the arrival of the olang, as the worms are known to the locals, terraces have been collapsing at an ever-increasing rate.

The worms can reach 18 inches in length and half an inch in diameter and are believed to have moved to the terraces as their original forest habitat was destroyed.